This imaginary monster, called Moz, has today been revealed as the official star of the £7m advert. It is shown hiding under the bed of Joe, a 7-year-old child who is woken by snoring and rumbling sounds beneath him.

Moz the Monster is the star of the 2017 John Lewis Christmas advertCredit:
John Lewis

Peeking beneath the bed he spots the 7ft creature snoozing, and the pair soon form a friendship where they play together every evening. These busy nights start to take a toll on Joe, whose exhaustion makes him fall asleep during afternoon football matches and haircuts.

After noticing his friend's dozy demeanour, on Christmas Day Moz gives Joe a night light that helps him fall asleep. But it also makes Moz disappear. Although sad that the friendship must come to an end to ensure he is able to sleep, at the end of the advert Joe is reminded that he can bring Moz back any time he wants by simply turning the light off.

The two-minute advert will premiere on TV screens this evening at around 9.30pm on Channel 4 and at the same time on all of Sky’s own channels. As with previous John Lewis adverts, it cost around £1m to shoot and a further £6m to cover marketing, in-store advertising and taking TV slots in advert-breaks.

The edit is produced by award-winning film director Michel Gondry, best known as director and writer of Eternal Sunshine of the Spotless Mind. The collaboration between Gondry and the retailer is highly lucrative for the latter thanks to Gondry's' expertise in producing highly-acclaimed commercials for the likes of BMW, Coca-Cola and Levi's.

Speaking about the John Lewis ad, Michel Gondry said: “When I told my ex-girlfriend I was doing the next John Lewis Christmas film she said; 'You have big shoes to fill, this John Lewis commercial must make people cry, don’t forget.' Last week I showed it to her and she cried. Phew.”

The musical score comes courtesy of Elbow, who cover The Beatles' Golden Slumbers, written by John Lennon and Paul McCartney. The song will also feature on Elbow’s ‘Best Of' album, which will be released on November 24.

Alongside the launch of the advert, John Lewis has produced five pieces of merchandise featuring Moz, including a children's book, gender-neutral pyjamas, and slippers, with prices ranging from £5 to £20.

This year's commercial follows a similar theme to that of last year's; of a child and an animal playing. A hound called Buster starred in last year's advert, accompanied by CGI animal characters including foxes, badgers, squirrels and hedgehogs, jumping on a trampoline.

Both ads, which are playful and uplifting, represent a steer away from the melancholy Man on the Moon advert of 2015, which fell flat with consumers who found it too bleak. Last year, a spokesperson for the department store said they would be moving away from so-called "sadvertising".

According to a Telegraph poll of more than 1,500 readers, the favourite John Lewis advert so far is the retail giant's first Christmas advert ever produced, in 2007, entitled Shadows.

The short film shows a group of employees placing products in a carefully assembled pile. All the items together end up creating a shadow that looks like a woman walking her dog through the snow.

According to forecasts by The Advertising Association, this Christmas will see the most ever spent on seasonal advertising by retailers, with advertisers investing close to £6bn during the final quarter of 2017, an increase of 37pc since 2010.

The trade association, working with Deloitte, found that every £1 spent on advertising returns more than £6 to the UK economy, and the industry supports nearly one million jobs.